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1.
Sci Rep ; 9(1): 12772, 2019 09 04.
Artículo en Inglés | MEDLINE | ID: mdl-31484972

RESUMEN

Female giant pandas show complex reproductive traits, being seasonally monoestrus, displaying a variable length embryonic diapause and exhibiting pseudopregnancy. Currently, there is no confirmatory non-invasive biomarker of blastocyst implantation or pregnancy. This study aimed to monitor urinary estrogens across gestation in pregnancy (n = 4), pseudopregnancy (n = 4) and non-birth cycles (n = 5) in the giant panda. A pregnancy-specific profile of estrogens corrected for urinary specific gravity was identified during the gestation period. Pregnant females showed increasing concentrations of estrogens for 29 days until birth, no increase was observed during pseudopregnancy and the two profiles were distinguishable from each other for the final 2 weeks of the cycle suggesting the estrogens are of placental origin. This allowed a nomogram, starting at a known fixed point during the cycle, to be created and tested with cycles of known outcome, and cycles which were inseminated but did not result in a birth. Non-birth profiles showed deviations from that of pregnancy. We believe these deviations indicate the point of failure of the placenta to support a developing cub. Non-invasive longitudinal monitoring of estrogen concentrations therefore has the potential to be developed as a panda pregnancy test to predict viable cub development.


Asunto(s)
Estrógenos/orina , Embarazo/orina , Ursidae/orina , Animales , Biomarcadores/orina , Femenino
2.
Invest Radiol ; 54(8): 500-516, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31058661

RESUMEN

OBJECTIVES: The aim of this study was to provide an ultrasound-based super-resolution methodology that can be implemented using clinical 2-dimensional ultrasound equipment and standard contrast-enhanced ultrasound modes. In addition, the aim is to achieve this for true-to-life patient imaging conditions, including realistic examination times of a few minutes and adequate image penetration depths that can be used to scan entire organs without sacrificing current super-resolution ultrasound imaging performance. METHODS: Standard contrast-enhanced ultrasound was used along with bolus or infusion injections of SonoVue (Bracco, Geneva, Switzerland) microbubble (MB) suspensions. An image analysis methodology, translated from light microscopy algorithms, was developed for use with ultrasound contrast imaging video data. New features that are tailored for ultrasound contrast image data were developed for MB detection and segmentation, so that the algorithm can deal with single and overlapping MBs. The method was tested initially on synthetic data, then with a simple microvessel phantom, and then with in vivo ultrasound contrast video loops from sheep ovaries. Tracks detailing the vascular structure and corresponding velocity map of the sheep ovary were reconstructed. Images acquired from light microscopy, optical projection tomography, and optical coherence tomography were compared with the vasculature network that was revealed in the ultrasound contrast data. The final method was applied to clinical prostate data as a proof of principle. RESULTS: Features of the ovary identified in optical modalities mentioned previously were also identified in the ultrasound super-resolution density maps. Follicular areas, follicle wall, vessel diameter, and tissue dimensions were very similar. An approximately 8.5-fold resolution gain was demonstrated in vessel width, as vessels of width down to 60 µm were detected and verified (λ = 514 µm). Best agreement was found between ultrasound measurements and optical coherence tomography with 10% difference in the measured vessel widths, whereas ex vivo microscopy measurements were significantly lower by 43% on average. The results were mostly achieved using video loops of under 2-minute duration that included respiratory motion. A feasibility study on a human prostate showed good agreement between density and velocity ultrasound maps with the histological evaluation of the location of a tumor. CONCLUSIONS: The feasibility of a 2-dimensional contrast-enhanced ultrasound-based super-resolution method was demonstrated using in vitro, synthetic and in vivo animal data. The method reduces the examination times to a few minutes using state-of-the-art ultrasound equipment and can provide super-resolution maps for an entire prostate with similar resolution to that achieved in other studies.


Asunto(s)
Medios de Contraste , Aumento de la Imagen/métodos , Microvasos/diagnóstico por imagen , Ovario/irrigación sanguínea , Ovario/diagnóstico por imagen , Fosfolípidos , Hexafluoruro de Azufre , Ultrasonografía/métodos , Algoritmos , Animales , Femenino , Humanos , Técnicas In Vitro , Microburbujas , Modelos Animales , Fantasmas de Imagen , Ovinos
3.
Endocrinology ; 156(4): 1494-503, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25635621

RESUMEN

Bone morphogenetic proteins (BMPs), members of the transforming growth factor ß (TGFß) superfamily, play important roles in folliculogenesis in various species; however, little is known about their role in luteal function. In this study, we investigated the expression, regulation, and effects of BMP2, BMP4, and BMP6 in carefully dated human corpora lutea and cultured human luteinized granulosa cells. The mRNA abundance of BMPs was increased in the regressing corpus luteum in vivo (P<.01-.001). Human chorionic gonadotropin (hCG) down-regulated BMP2, BMP4, and BMP6 transcripts both in vivo (P=.05-.001) and in vitro (P<.001), and decreased the mRNA abundance of BMP receptors (BMPR1A, BMPR1B, BMPR2; P<.05-.01) in vitro. Three BMPs were regulated by differential signaling pathways. H89, a protein kinase A inhibitor, increased the expression of both BMP2 (P<.05) and BMP4 (P<.05) while decreasing BMP6 (P<.01). PMA, a protein kinase C activator, decreased both BMP4 and BMP6 expression (P<.0001) while enhancing the mRNA abundance of BMP2 (P<.01). BMPs significantly down-regulated transcripts for LH/choriogonadotropin receptor (LHCGR; P<.001) and steroidogenic acute regulatory protein (STAR; P<.001), whereas up-regulating those of follicular stimulating hormone receptor (FSHR; P<.01) and aromatase (CYP19A1; P<.05-.01) in vitro, possessing an effect opposite to hCG but similar to Activin A. Like Activin A, BMP4 and BMP6 stimulated the expression of Inhibin/Activin subunits with a marked effect on INHBB expression (P<.05-.01). These data confirm that BMPs are increased during luteal regression and negatively regulated by hCG via differential mechanisms, suggesting that BMPs are one of the mediators of luteolysis in women.


Asunto(s)
Proteínas Morfogenéticas Óseas/metabolismo , Cuerpo Lúteo/metabolismo , Células de la Granulosa/metabolismo , Luteólisis/metabolismo , Aromatasa/genética , Aromatasa/metabolismo , Proteínas Morfogenéticas Óseas/genética , Gonadotropina Coriónica/farmacología , Cuerpo Lúteo/efectos de los fármacos , Femenino , Células de la Granulosa/efectos de los fármacos , Humanos , Isoquinolinas/farmacología , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Receptores de HFE/genética , Receptores de HFE/metabolismo , Transducción de Señal/efectos de los fármacos , Sulfonamidas/farmacología
4.
BMC Pregnancy Childbirth ; 13: 30, 2013 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-23369098

RESUMEN

BACKGROUND: The current measure of treatment efficacy of single-dose methotrexate for ectopic pregnancy, is a fall in serum hCG of ≥15% between days 4-7 of treatment, which has a positive predictive value of 93% for treatment success. Two small studies have proposed a fall in serum hCG between days 0-4 after treatment confers similar, earlier prognostic information, with positive predictive values of 100% and 88% for treatment success. We sought to validate this in a large, independent cohort because of the potentially significant clinical implications. METHODS: We conducted a retrospective study of women (n=206) treated with single-dose methotrexate for ectopic pregnancy (pre-treatment serum hCG levels ≤3000 IU/L) at Scottish hospitals between 2006-2011. Women were divided into two cohorts based on whether their serum hCG levels rose or fell between days 0-4 after methotrexate. Treatment outcomes of women in each cohort were compared, and the test performance characteristics calculated. This methodology was repeated for the current measure (≥15% fall in serum hCG between days 4-7 of treatment) and an alternate early measure (<20% fall in serum hCG between days 0-4 of treatment), and all three measures were compared for their ability to predict medical treatment success. RESULTS: In our cohort, the positive predictive value of the current clinical measure was 89% (95% CI 84-94%) (121/136). A falling serum hCG between days 0-4 predicted treatment success in 85% (95% CI 79-92%) of cases (94/110) and a <20% fall in serum hCG between days 0-4 predicted treatment success in 94% (95% CI 88-100%) of cases (59/63). There was no significant difference in the ability of these tests to predict medical treatment success. CONCLUSIONS: We have verified that a decline in serum hCG between days 0-4 after methotrexate treatment for ectopic pregnancies, with pre-treatment serum hCG levels ≤3000 IU/L, provides an early indication of likelihood of treatment success, and performs just as well as the existing measure, which only provides prognostic information on day 7.


Asunto(s)
Abortivos no Esteroideos/administración & dosificación , Gonadotropina Coriónica/sangre , Metotrexato/administración & dosificación , Embarazo Ectópico/tratamiento farmacológico , Adulto , Gonadotropina Coriónica/metabolismo , Estudios de Cohortes , Femenino , Humanos , Valor Predictivo de las Pruebas , Embarazo , Embarazo Ectópico/sangre , Estudios Retrospectivos , Resultado del Tratamiento
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